olmsted



(No Model.)

B. P. OLMSTED. A

GUT-OPP VALVE. No. 301,142. Patented July 1,1884.

"ol e Jil: wx WN E' NSNW WITNESSBS: l mvmo C BY` ATTORNEY UnrTnb FTaTrs BENJAMIN F. OLMSTED, OF GRAND RAPIDS, MICHIGAN, ASSIGNOR TO SARAHA FaTnNT Traer.

L. OLMSTED, OF SAME PLACE.

CUT-OFF VALVE.

SPBCII'CATION forming part of Letters Patent No. 301,142, dated July l, 1884.

Application filed March 14, 1884. (No morlcL) city of Grand Rapids, in the county ol' Kenty and State of Michigan, have invented certain new and useful Improvements in Automatic Cut-Off Valves for Steam-Engines, of which the following is a specification.

My invention relates to improvements in cut-off valves for steam-engines, and more especially to improvements in the cutoff valve patented to me September 4, 1883, and theobject of my invention is to render more effective and useful the principle embodied in the invention so patented to me. .l attain this object by means of the mechanism illustrated in the accompanying drawings, in which- Figure l is a vertical sectional view of my `invention (with such other parts of an engine as are attached to the part by me invented)v on theline Y Y of Fig. 2. Fig. 2 is a vertical sectional view ofthe same on line X X of' Fig. 1. Fig. 3 is a plan view of cushion-cylinders and piston, with the left-hand cylinder in section, so as to show the form of the piston and internal arrangement for cushioning the valve, as fully described below. Fig. 4: is a skeleton view of a double valve with parts separated a considerable distance from each other. Fig. 5 is a side elevation of the same part shown by plan view in Fig.

Similarletters refer to similar parts throughont the several views.

In the drawings, L is the compression-rod operated by the governor, which governor is not shown in the drawings, as it is no part of my invention. A spring may be applied to counteract the pressure from the governor similar to springs now in use.

U is a piston, so placed that it is depressed by the action of the rod L, and in turn de presses the parallel planes T T, which planes are placed above the rollers 10 and in contact with them, as shown in Fig. 2.

A A are the journals of the roller 10. rlhe roller 10, with the blades B B journaled upon A, is also depressed through the piston U and planes T T by the action of the rod L. The operation thus far is identical with the operation shown in my cut-offvalve, patented Sep tomber 4A, 1883, above referred to.

H is a cut-off valve, so constructed that it receives the sliding blade B and its upper end oscillates its lower end or bearing, being held in a groove, as shown in Fig. 1.

13 13 18 are springs placed in openings in valve H, beneath the edge of the blade, so as to press outwardly on the blade and to press the roller 10 into the arc or socket formed by the yoke M, and when the engine is notin motion to hold it there, being theposition shown in Fig. 1. The upper socket beneath M, as well as thelower arch shown in Fig. 1` is the same as shown'in my previous patent; but the valve H in my present in vention has its resting point at its bottom, as above described.

n n a are vents in the valve H to allow the steam to enter and surround the blade and hold itin equilibrium.

D is anordinary D-valve.

S and S aresteam-ports, which receive the steam from the steam-passages F and F and convey it to the cylinder, thereby creating a current of steam alternately through the passages F and FQ which steam-current acts first on one wing of H and then on the other.

J J are steam-vents, for the purpose of equalizing the steam-pressure on valve H, allowing the springs 13 to bring the valve to its normal position, when the pressure is equalilzed.

E is an exhaust for main Dvalve.

G is the steam governor chest, resting on the top of D of the main-steam-chest.

au a are vent-holes extending through the piston U and the base of the steam governor chest, in order to equalize the steam-pressure in the steam governor chest G, as also over and around the governor-piston.

K K are journals on which the valve H turns or oscillates. The sockets beneath M may or may not be the arcs of a circle, but the ares are so placed that as the roller 10 passes from the upper arc to the lower one it passes over an angle or obstacle. The valve H has two wings, 1 and 1one on either side, as shown in Fig. l-wing 1 seating on passage F, and wing 1 seating on FC The object-of this construction is to bring the valve more quickly to the valve-seat, and decrease its oscillatory motion. The dotted lines in Fig. 1 show the position of the valve when seated on F. Just back of the yoke M are placed the steanncush ion cylinders 2 and 2', with double piston. In each ofthe cushion-cylinders is a piston, and each piston `is precisely like the other, and they are connected by a bridge, 7, thus making them act as a double piston.

1l .isa shoulder on the pistou, and LI is the small portion of the pistou that projects be-A yond the shoulder, and is surrounded bythe spiral spring 6. One end ot' this spring` rests against the shoulder l1 and one end against the screw 3, which screw adjusts the piston to the required position, the piston moving in the screW3 longitudinally. By turning sere-W 3 in one direction the spring (5 is compressed,

and by turning it in the other direction the pressure is lessened.

12 and I2 are shoulders on the piston, and they are shown by dotted lines in Fig. I.

5 and 5 are portions of the piston that pass into the cylinder 2 and 2.

8 and 8 are steam-vents in the cushion-cylinders for admitting steam to equalize the pressure in such cylinders and to form a steamcnshion in each. The object of the springs is merely to hold the pistons in position, so as to have the steam space in each steamcnshion cylinder equal, and in ease a strong spring is used the spring acts also as a cushion.

The operation of my invention is as follows: When the engine is set in motion, as the speed increases, the governor-rod L depresses the piston U, planes T T, and roller IO until the steam, entering the cylinder through port S', causes a current in F, which carries the wing l of valve H to its valve-seat, as shown by the dotted lines in Fig. lf Just before the Wing l reaches its seat the stem of'valve H is brought in contact with the shoulder 12 on the cushion-piston in cushion-cylinder 2, thus re- .tarding the motion of the valve H, and bringing the Wing l to its seat Without pounding. The Wing 1, reaching its seat, cuts off the steam :from passage F', and as the main D `valve reverses its motion the steam, prior to the opening of port S, passes by means of vent J into passage F, when the spring brings H to .its normal position, as shown in Fig. l, and

when S is opened a reverse current is created, and Wing I of valve I-I is carried to its seat, its stroke being modified by the contact oi the stem of valve H with shoulder l2 of the cushion-piston, and the operation is thus continued and the steam is alternately cut 01T from passages F and F. In long D-valves I use the same principle, but separate the Wings I and I from the stem of the valve, and conneet them thereto by means of connecting rods 9 and 9', as shown in Fig. 4.

The operation of the device shown in Fig. 4 is precisely the same as that shown in Fio. l, and I use the cushion-cylinders and piston in the same manner.

Having thus described my invention, what I lclaim to have invented, and desire to secure by Letters Patent, is-

I. In an automatic cnt-off valve, the oseillating valve H, provided with the Wings l and l', in combination with the sliding blade B, springs I3 13 I3, roller 10, and socket under yoke M, all substantially as described.

2. The combination of the automatic oscillating valve H, the piston 7, provided With shoulders I2 and 12', and shoulder 11, the adjustable screws 3 and 3', cushion-cylinders 2 and 2', and springs 6 6, all substantially as described.

3. The combination of the separated ivings v1 and l', as shown, the blade B, valve-stein HQ and connecting-rods 9 and 9, for the purpose set forth.

BENJAMIN F. OLMSTED. Witnesses:

EDWARD TAGGART, FRED W. STEvnNs. 

